Recent in vitro [24] and preclinical in vivo [25] studies have focused on the early molecular biological responses to various titanium implant surfaces. Understanding these early responses is essential for efforts aiming to accelerate and enhance the process of osseointegration [26]. Upregulation or downregulation of specific genes in peri-implant tissues identified by analyses of genetic material (DNA, RNA) reflects the nature and timing of the various healing processes, which in turn could be potential ‘molecular targets’ for enhancing osseointegration [27,28]. The aim of the present study was to systematically review the available literature on gene expression analyses of the biological processes involved in early human peri-implant bone healing.